Field of the Invention
Embodiments of the present invention relate to power control of a heating member included in a fixing unit.
Description of the Related Art
An electrophotographic method image forming apparatus forms an image on a sheet using toner, melts the toner by heat generated by a heating member installed in a fixing unit, and fixes the image on the sheet. The fixing unit is provided with a sensor for detecting a temperature of the heating member, and power supplied to the heating member is controlled so that the temperature of the heating member detected by the sensor will be a target temperature.
For example, an image forming apparatus described in Japanese Patent Application Laid-Open No. 2007-241155 controls power supplied to a heating member based on a difference value between a target temperature and a temperature of the heating member and an accumulated value of the difference values between the target temperature and the temperature of the heating member so as to control the power supplied to the heating member. The image forming apparatus uses a different operation coefficient according to an operation mode. According to the image forming apparatus described in Japanese Patent Application Laid-Open No. 2007-241155, an operation coefficient used in a period from when power is supplied to the heating member to when a temperature of a heater reaches a printable temperature and an operation coefficient used in printing are different. Embodiments of the present invention are directed to control of power supplied to a heating member with high accuracy.